Easy to stretch, coated with the special material that prevents rapid wear and tear, well preserved from sun rays and sea salt. I could not locate on Kent website how they make their rubber. Speargun manufactures don't make their own rubber let alone most of their spear. I was not saying it didn't. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register. The reason Ulusub uses Kent Elastomer for our Rubber is twofold.